Page:Popular Science Monthly Volume 83.djvu/305

when you start you think your breakfast will last all day, becomes of vital importance about the time the sun is directly over your head, when you will devour every crumb, and, like poor Oliver, cry for more. Carry a little india rubber, leather or tin drinking-cup with you but don't put much water inside of you—it is deleterous during these tramps; once give way to the temptation of guzzling creek water and by the time you are ready to drag yourself home, you will be as near a gone case of foundering as any undertaker need delight to see. If you feel thirsty smoke segars, if you can't smoke moisten your lips with a little lemon-juice or whisky, but don't moisten with too much of the latter so that the last seen of you is adorning the corner of some fence, with the flies hovering around your mouth trying to ascertain whether it was "Mountain Dew" or "Lavan's Best Proof" that has put you in a position for your friends to be ashamed of you, sir.

How detailed and considerate the instructions are! That these old naturalists were proud of their outfits, we can judge from the fact that Linnæus, the passed master of them all, had his portrait painted in his Lapland collecting costume. There are many descendants of these worthies at this board to-night, but where among us is a single representative. As Joseph Jefferson once said in describing his own person, we find ourselves disguised in the clothes of gentlemen, and no one here this evening has moistened his lip with "Mountain Dew," not to mention lemon-juice.

But what did these old masters do for us? They undertook and partly performed the enormous task of delivering to us a descriptive catalogue of the animals and plants of the world. To be sure this seemed a simpler proposition in the old days when, as Linnaeus declared, there were as many species as had been created in the beginning. But even then the number must have seemed considerable, for Linnaeus himself gave us descriptions of over four thousand species of animals. Probably, however, he had no suspicion that the total of described animals alone was to rise in our day to half a million and even after this heavy draft, nature would still have the appearance of inexhaustibleness.

But nature is not only vastly richer in species than the older naturalists probably suspected; she is continually at work creating new forms. The simple faith of Linnaeus in the special creation of animals and plants was forever overthrown by Darwin, whose "Origin of Species" established a new point of view for this whole question. And recent evolutionary work has shown that organic transformation is not only in progress to-day, as it has been in the past, but, in the hands of man, it is rapidly assuming the aspect of an important element in civilization. Within the last few years such mastery has been gained over the factors controlling the color of the hair of some of our smaller and more rapidly breeding mammals that, within reasonable limits, a pure breed of guinea pigs of a previously designated color, for instance, can be produced in an incredibly short time. And when it is kept in mind that some of the colors thus produced had long been sought in vain by the old--